The present invention relates to rescue equipment for submarine crafts wherein a chemical reaction or a catalytic decomposition of a liquid produces gas which establishes the or additional static lift.
U.S.-Letters Pat. No. 3,942,456 discloses such a rescue equipment which includes a plurality of gas generators being preferably disposed in the ballast tanks of the submarine craft in order to blow these tanks when the need arises. The gas generators in particular provide gas by chemical reaction and/or by catalytic decompositioning, and the generated gas blows the tanks to obtain the requisite buoyancy permitting, hopefully, that the possibly disabled vehicle can still surface. In accordance with this particular patent, one provides a plurality of such gas generators and operates them in a number corresponding to the particular depth from which the craft is to surface. The particular equipment includes particularly equipment for automatically selecting the number of generators to be activated in dependence upon the depth of the craft when the need arises. As a particularly advantageous embodiment, gas generators are described in this patent in which the liquid reactant is forced into and through a catalyst under pressure to obtain the catalytic reaction and decompositioning. Equipment of the type disclosed in the above-identified patent has actually been used and found operational and adequately functioning.
It was found, however, that after a successful surfacing of the submarine craft, it may be necessary to blow additional gas into the tanks because the gas resulting from the chemical reaction or catalytic decompositioning cools after filling the tank and that cooling reduces its volume. Also, one or the other components resulting from the reaction or the decompositioning may be water soluble and may mix to some extent with the water in the ballast tank, and again, the resulting effective gas volume produced is less than what is expected. Moreover, the vessel may vibrate, shake or undergo other irregular movements resulting in a partial discharge of the gas from the tanks without adequate replacement.